Mariners vs Red Sox Prediction, Odds, Moneyline, Spread & Over/Under for June 18

Odds updated as of 4:13 a.m.

The Seattle Mariners will face the Boston Red Sox in MLB action on Wednesday.

We've got you covered, in terms of the most important information regarding this matchup before you take a look at the MLB odds and spreads on FanDuel Sportsbook.

Mariners vs Red Sox Game Info

• Seattle Mariners (37-35) vs. Boston Red Sox (38-37)
• Date: Wednesday, June 18, 2025
• Time: 4:10 p.m. ET
• Venue: T-Mobile Park -- Seattle, Washington
• Coverage: MLB Network, ROOT Sports NW, and NESN

Mariners vs Red Sox Odds & Moneyline

• All MLB odds, betting lines and prop bets are available on FanDuel Sportsbook.
• Moneyline: SEA: (-162) | BOS: (+136)
• Spread: SEA: -1.5 (+134) | BOS: +1.5 (-162)
• Total: 7 -- Over: (-122) | Under: (-100)

Mariners vs Red Sox Probable Starting Pitchers

Probable Pitchers: Luis Castillo (Mariners) - 4-4, 3.29 ERA vs Garrett Crochet (Red Sox) - 6-4, 2.24 ERA

The Mariners will give the nod to Luis Castillo (4-4, 3.29 ERA), who is eyeing win No. 5 on the season, and the Red Sox will turn to Garrett Crochet (6-4, 2.24 ERA). Castillo and his team are 6-8-0 ATS this season when he starts. Castillo's team has been victorious in 50% of the games he's started as the moneyline favorite with a record of 6-6. When Crochet starts, the Red Sox have gone 7-8-0 against the spread. The Red Sox were the underdog on the moneyline for one Crochet start this season -- they won.

Mariners vs Red Sox Prediction & Pick

All MLB win probability predictions and picks are according to numberFire.
Prediction: Red Sox win (50.8%)

Mariners vs Red Sox Moneyline

• Looking at the moneyline for Mariners-Red Sox, Seattle is the favorite at -162, and Boston is +136 playing on the road.

Mariners vs Red Sox Spread

• The Mariners are hosting the Red Sox and are favored by 1.5 runs on the spread. The Mariners are +134 to cover the runline, with the Red Sox being -162.

Mariners vs Red Sox Over/Under

• Mariners versus Red Sox on June 18 has an over/under of 7 runs, with the odds on the over -122 and the under set at -100.

Bet on Seattle Mariners vs. Boston Red Sox on FanDuel today!

Mariners vs Red Sox Betting Trends

• The Mariners have won in 24, or 52.2%, of the 46 contests they have been named as odds-on favorites in this year.
• This year Seattle has won seven of 14 games when listed as at least -162 on the moneyline.
• The Mariners and their opponents have gone over the total this season in 37 of their 71 opportunities.
• The Mariners have posted a record of 31-40-0 against the spread this season.
• The Red Sox have gone 12-13 in games they were the underdog on the moneyline (winning 48% of those games).
• In games it has played as a moneyline underdog with odds of +136 or longer, Boston has gone 5-3 (62.5%).
• The Red Sox have combined with opponents to go over the total 34 times this season for a 34-39-2 record against the over/under.
• The Red Sox have put together a 39-36-0 record against the spread this season.

Mariners Player Leaders

• Cal Raleigh leads Seattle with 70 hits, batting .266 this season with 40 extra-base hits. He has an on-base percentage of .374 and a slugging percentage of .624.
• Among qualifying hitters in MLB, his batting average ranks 59th, his on-base percentage ranks 22nd, and he is third in slugging.
• Julio Rodriguez has hit 10 homers this season while driving in 34 runs. He's batting .258 this season and slugging .412 with an on-base percentage of .321.
• Among qualified hitters, his batting average places him 74th, his on-base percentage 94th, and his slugging percentage 94th.
• J.P. Crawford leads Seattle in OBP (.416) this season, fueled by 72 hits.
• Jorge Polanco has 11 home runs, 36 RBI and a batting average of .259 this season.

Red Sox Player Leaders

• Jarren Duran has a team-high .417 slugging percentage. He's batting .261 with an on-base percentage of .316.
• Including all the qualified hitters in MLB, his batting average puts him 69th, his on-base percentage ranks 103rd, and he is 87th in slugging.
• Ceddanne Rafaela is hitting .247 with 11 doubles, two triples, six home runs and 14 walks. He's slugging .385 with an on-base percentage of .296.
• He is currently 96th in batting average, 130th in on-base percentage and 117th in slugging percentage among all qualified hitters.
• Carlos Narvaez is hitting .277 with 15 doubles, six home runs and 26 walks.
• Trevor Story is batting .230 with seven doubles, nine home runs and 14 walks.

Mariners vs Red Sox Head to Head

• 6/17/2025: 8-0 SEA (Favorite: Mariners, Spread: -1.5, Total: 7, Favorite Moneyline: -162, Underdog Moneyline: +136)
• 6/16/2025: 2-0 BOS (Favorite: Mariners, Spread: -1.5, Total: 7, Favorite Moneyline: -178, Underdog Moneyline: +150)
• 4/24/2025: 4-3 SEA (Favorite: Red Sox, Spread: -1.5, Total: 8, Favorite Moneyline: -180, Underdog Moneyline: +152)
• 4/23/2025: 8-5 SEA (Favorite: Red Sox, Spread: -1.5, Total: 9.5, Favorite Moneyline: -136, Underdog Moneyline: +116)
• 4/22/2025: 8-3 BOS (Favorite: Red Sox, Spread: -1.5, Total: 9.5, Favorite Moneyline: -122, Underdog Moneyline: +104)
• 7/31/2024: 3-2 BOS (Favorite: Mariners, Spread: -1.5, Total: 9.5, Favorite Moneyline: -112, Underdog Moneyline: -104)
• 7/30/2024: 10-6 SEA (Favorite: Mariners, Spread: -1.5, Total: 10.5, Favorite Moneyline: -118, Underdog Moneyline: -100)
• 7/29/2024: 14-7 BOS (Favorite: Red Sox, Spread: -1.5, Total: 8.5, Favorite Moneyline: -120, Underdog Moneyline: +102)
• 3/31/2024: 5-1 BOS (Favorite: Mariners, Spread: -1.5, Total: 7.5, Favorite Moneyline: -120, Underdog Moneyline: +102)
• 3/30/2024: 4-3 SEA (Favorite: Mariners, Spread: -1.5, Total: 7, Favorite Moneyline: -164, Underdog Moneyline: +138)

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